A lot of people think bad, immoral behavior is unique to Man; only the human race could do the evil things that it does. Animals, on the other hand, are believed to be cute and innocent and free of such flaws.

That’s not always the case. Animals do just as Man sometimes does – they kill for kicks, they cheat on their mates, they pick on the weak and they abandon their kids.

It’s that last trait that presents itself in the form of the brown headed cowbird, the ultimate deadbeat parent of the animal kingdom.

Identifying the cowbird

Cowbirds look like blackbirds with brown heads. (PHOTO COURTESY OF

NATUREPICSONLINE.COM)

Cowbirds are squat birds -- 6 to 8 inches long -- that look like short blackbirds. The male has a jet black body with a glossy brown head. The female is among the dullest of local birds, sporting mostly a plain, grayish hue with a lighter throat. They have short, fat bills that look like the seed cracking beaks of finches.

Their songs are rather intriguing for such a plain bird. The male can often be heard making a melodic gurgling sound as he spreads his wings and tailfeathers to show his physical and sexual dominance. Birds of both sexes will make a high-pitched sound, described as weee-tiiii, as a general call, variations of which will warn of danger or the lack thereof.

Where to find cowbirds

The cowbird is found throughout the Niagara Frontier.

They will frequent cities and villages (like Lockport and Middleport) in somewhat low numbers. If you maintain a bird feeder in the summer, you might have had them as guests dining on sunflower seeds.

You are likely to encounter them in our rural communities, especially those with dairy farms, like Gasport where they can be fairly common, sometimes even abundant.

They get the name of cowbird from their tendency to live near and with livestock. Rather than feeding on the feed of cows as starlings will, cowbirds choose instead to closely follow cows and eat the bugs kicked up by their hooves or frequenting their manure. They will even land on cows’ backs and pick bugs off of them.

Before cows became a part of the Eastern landscape, cowbirds were mostly confined to the central grasslands and associated with herds of bison.

Deadbeat parenting

It’s that affinity for bison, which were incredibly nomadic, that led to the cowbird’s propensity for deadbeat parenting. Ornithologists believe that in order to keep pace with the herds, and not having time to incubate eggs -- let alone make a nest -- cowbirds used other birds to tend for their young, which is what they still do to this day.

The brown-headed cowbird and its cousin the bronzed cowbird are the only brood parasites on this continent. The female cowbird will find a nest being tended to by another bird and patiently wait for the mother bird to leave for a feeding. Once the bird has left the cowbird deposits up to 5 speckled eggs in the nest and then leaves the scene for good.

Cowbirds are known to do this to over 200 species of birds, with mostly disastrous effects. The unknowing caretaker treats the egg and the hatchlings as her own. Baby cowbirds grow quickly and are typically bigger than the host species. So, the baby cowbird will outcompete the other baby birds for attention and/or food, which will starve the smaller species or cause them to get pushed out of the nest by the larger cowbird.

I’m seeing that in my backyard right now. A song sparrow that should have been tending to at least 2 babies of her own has instead been feeding a cowbird that is now out of the nest. The sparrow still tends to the cowbird – the gig isn’t up even though the cowbird is twice the adult sparrow’s size.

Come fall, the newly fledged cowbirds will join up with flocks of other cowbirds and head south for the winter, only to return again the next year and do their thing all over again.

Over the years, it has been frustrating to witness their impact on songbirds (especially catbirds and cardinals) in the Gasport area as they have accounted for the deaths of thousands of birds.

But, there is some hope in sight. The most recent edition of the New York State breeding bird atlas found cowbird populations down 7% between 1985 and 2005, continuing a downward trend that began in the mid-1960s as more family farms (and their token small flocks of cattle) were replaced by grain fields or forests.

If the population trend continues, maybe someday soon some of our more attractive local songbirds will have a chance to raise their own young and reverse their own population declines.

1 comment:

I had a cowbird lay an egg in a robin's nest on my porch a couple years ago. They pushed all but one robin egg out and laid one egg. The robins ended up abandoning the nest. A few days later a house finch built her nest inside the robin's nest, leaving the one robin egg and one cowbird egg in the bottom of the old nest. She laid 4 or 5 eggs and was able to hatch one but because that cowbird egg was underneath it still hatched. The baby cowbird was so big compared to the baby house finch. She fed both for 2 or 3 days and then the baby house finch was gone. I never found it anywhere and look all over and around the porch but it was gone. Mama house finch continued to feed the baby cowbird for another week or two. The baby cowbird had all of its feathers and was losing its down when the mama house finch stopped feeding it and it ended up dying in the nest a couple days later. I felt bad for it because a life is a life no matter how it survives. I have not had any birds make a nest on my porch since. I have pictures from it. I tried to document it on Facebook as best I could at the time.